Eucalyptus-Based Glued Laminated Timber: Evaluation and Prediction of Its Properties by Non-Destructive Techniques
Ramon Ferreira Oliveira,
Pedro Gutemberg de Alcântara Segundinho,
João Gabriel Missia da Silva,
Fabricio Gomes Gonçalves,
Dercílio Junior Verly Lopes,
Jeferson Pereira Martins Silva,
Nayara Franzini Lopes,
Leonor da Cunha Mastela,
Juarez Benigno Paes,
Clara Gaspar Fossi de Souza,
Francisco Antônio Rocco Lahr,
Maria Alice Romanha Belumat,
André Luis Christoforo,
Caroline Palacio de Araujo
Affiliations
Ramon Ferreira Oliveira
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
Pedro Gutemberg de Alcântara Segundinho
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
João Gabriel Missia da Silva
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
Fabricio Gomes Gonçalves
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
Dercílio Junior Verly Lopes
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
Jeferson Pereira Martins Silva
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
Nayara Franzini Lopes
Department of Forest Engineering, Federal University of Viçosa, Avenida P. H. Rolfs, s/n, Viçosa 36570-900, MG, Brazil
Leonor da Cunha Mastela
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
Juarez Benigno Paes
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
Clara Gaspar Fossi de Souza
São Carlos School of Engineering, University of São Paulo, Avenida Trabalhador São Carlense, 400, Parque Arnold Schimidt, São Carlos 13566-590, SP, Brazil
Francisco Antônio Rocco Lahr
São Carlos School of Engineering, University of São Paulo, Avenida Trabalhador São Carlense, 400, Parque Arnold Schimidt, São Carlos 13566-590, SP, Brazil
Maria Alice Romanha Belumat
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
André Luis Christoforo
Department of Civil Engineering, Federal University of São Carlos, Rodovia Washington Luís, km 235, s/n, Jardim Guanabara, São Carlos 13565-905, SP, Brazil
Caroline Palacio de Araujo
Departament of Forest and Wood Science, Federal University of Espírito Santo, Avenida Governador Lindemberg, Jerônimo Monteiro 29550-000, ES, Brazil
Eucalyptus-based glued laminated timber (glulam) was produced to determine the feasibility of a non-destructive method (drilling resistance) to predict the properties of structural elements and add value to lower-quality hardwood species. Glulam was manufactured with formaldehyde (Resorcinol), reference condition, and bio-based (Castor oil-based) adhesives in two assembly schemes, the core composed either of two continuous lamellae each 105 cm long, or of two formed by the juxtaposition of shorter boards (35 and 55 cm). The shear strength of the glue line (fv0), modulus of elasticity (Ec90), and strength (fc90) in compression perpendicular to the grain; delamination (DL); and main and extended glue line thicknesses were evaluated. The Resistograph equipment was used to perform the perforation perpendicular to the glue line (samples extracted from the glulam elements) to correlate the properties. The results of this research demonstrate that the scheme of the boards had little effect on the physical and mechanical properties evaluated (except the main glue line and delamination), and the drilling resistance (DR) presents a significant correlation with practically all properties evaluated (variations in density values and other properties are explained by variations in DR values), making it possible to estimate Ec90 and fc90 with desired precision (R2adj ≈ 80%). This highlights the feasibility of using this methodology in the quality control of glulam elements. It is concluded that regardless of the adhesive, elements comprising a 105 cm-length core and external lamellae (T1 and control) are indicated for external use, presenting low delamination. Short-length central lamellae adhesively glued with PUR (T2) are not recommended for external applications due to their susceptibility to delamination. However, T2 is indicated for internal environments due to its low production cost. This study also proved the efficiency of using models based on drilling resistance to estimate wood density and its resistance to compression perpendicular to the fiber.
